Varying this setting allows IGMPv2 routers to tune the "leave
latency" (the time between the moment the last host leaves a group
and when the routing protocol is notified that there are no more
members), as discussed in section 7.8. It also allows tuning of the
burstiness of IGMP traffic on a subnet, as discussed in section 7.3

It should say:

Varying this setting allows IGMPv2 routers to tune the "leave
latency" (the time between the moment the last host leaves a group
and when the routing protocol is notified that there are no more
members), as discussed in section 8.8. It also allows tuning of the
burstiness of IGMP traffic on a subnet, as discussed in section 8.3

Notes:

Section 2.2 2nd para refers to section 7.8 and 7.3 neither of which
exist. It should refer to 8.8 and 8.3.

Resetting timer is obviously different than setting timer.
--VERIFIER NOTES--
I am rejecting this Erratum mainly because RFC 2236 has been obsoleted by RFC 3376, but also because I don't agree that the change is needed. The original text covers the two operations adequately.